The U.S. Chemical Safety Board’s animated video (above) on the explosions at the Arkema Chemical Plant in Crosby recounts the steps taken by the brave workers stuck in charge of the facility in the aftermath of Hurricane Harvey. But a few angles less charitable to the company’s emergency planning effort aren’t included — possibly because they’d be a little more involved to animate. For example, the noxious fumes that emanated from the first fire, on the night of August 31, which according to a lawsuit filed later Arkema gave no warning about — and sent 23 people to the hospital, many of them vomiting and gasping for cleaner air.

And another detail: The remote detonations of 6 trailers containing unrefrigerated organic peroxides were carried out by the Houston Police Department’s bomb squad. “The entire police operation was conducted without warning the public,” write the Houston Chronicle‘s Matt Dempsey and Jacob Carpenter. “Until the documents were released earlier this month by the EPA, the public didn’t know who performed the controlled burn, or how it was done.”

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Dempsey and Carpenter report that government officials were particularly concerned that a tank containing isobutylene might fail when the organic peroxides were set on fire, triggering a chain reaction involving a separate sulfur dioxide tank and creating a “toxic cloud.” “Arkema’s risk-management plan said such a reaction could affect more than a million Houston-area residents,” they write. “The concern was so great that the bomb squad set fire to the remaining trailers farthest from the isobutylene first, just to be sure. The tank was not damaged and did not catch fire.“